Flagship program

The Flagship Program is a series of NASA missions to explore the Solar System. It is the largest and most expensive of three classes of NASA Solar System Programs, the other two being the medium-cost New Frontiers Program and the lowest-cost Discovery Program.

According to NASA, the cost of a Flagship-class mission is over $1 billion. These missions will be crucial in allowing humans to reach and explore high-priority targets. These critically important targets could help establish the limits of planetary habitability, not just for the Solar System, but for planetary systems in general. In particular, they potentially provide an opportunity to identify prebiotic organic molecules or even extant life beyond Earth, should it exist, in the Solar System. The targets of Flagship missions may include complex missions to the atmosphere and surface of Venus, the lower atmosphere and surface of Titan, the surface and subsurface of Europa, the stormy atmosphere of Jupiter, the dusty surface of Mars, the ring systems of Saturn, the deep atmospheres of the ice giants Neptune and Uranus, the surface of the moon Triton, the plumes of Enceladus, the surface and magnetosphere of Mercury, and the surface of a comet nucleus in the form of cryogenically preserved samples.

The Flagship program includes the Viking probes (1975), the Voyager probes (1977), the Galileo spacecraft (1989), the Cassini spacecraft (1997), the Chandra X-Ray Observatory (1999), and the Mars Science Laboratory (2011). Proposed programs in the estimated range $1 billion and $3 billion include the Mars 2020, and Europa Multiple-Flyby Mission (2022).

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